Αποτελεσματική Πεδιακή Θεωρία
Φαινομενολογική Πεδιακή Θεωρία Effective Field Theory, List of quantum field theories *''Καμία σχέση με την Φαινομενική Πεδιακή Θεωρία (Phenomenal)'' thumb|300px| [[Επιστημονική Θεωρία ---- Φυσικές Θεωρίες Χημικές ΘεωρίεςΓεωλογικές Θεωρίες Βιολογικές Θεωρίες Οικονομικές Θεωρίες ]] thumb|300px| [[Επιστημονική Θεωρία ---- Φυσική Θεωρία Χημική Θεωρία Γεωλογική Θεωρία Βιολογική Θεωρία Οικονομική Θεωρία ]] thumb|300px| [[Επιστημονική Θεωρία ]] thumb|300px| [[Επιστημονική Θεωρία ]] - Μια Πεδιακή Θεωρία. Ετυμολογία * Η ονομασία "πεδιακή" σχετίζεται ετυμολογικά με την λέξη "Πεδίο". * Η ονομασία "Φαινομενολογική" σχετίζεται ετυμολογικά με την λέξη "Φαινομενολογία". Εισαγωγή In physics, an effective field theory is a type of approximation to (or effective theory for) an underlying physical theory, such as a quantum field theory or a statistical mechanics model. An effective field theory includes the appropriate degrees of freedom to describe physical phenomena occurring at a chosen length scale or energy scale, while ignoring substructure and degrees of freedom at shorter distances (or, equivalently, at higher energies). Intuitively, one averages over the behavior of the underlying theory at shorter length scales to derive what is hoped to be a simplified model at longer length scales. Effective field theories typically work best when there is a large separation between length scale of interest and the length scale of the underlying dynamics. Effective field theories have found use in *particle physics, *statistical mechanics, *condensed matter physics, *general relativity, and *hydrodynamics. They simplify calculations, and allow treatment of dissipation and radiation effects ."Classical Mechanics of Nonconservative Systems" by Chad Galley"Radiation reaction at the level of the action" by Ofek Birnholtz, Shahar Hadar, and Barak Kol The renormalization group Presently, effective field theories are discussed in the context of the renormalization group (RG) where the process of integrating out short distance degrees of freedom is made systematic. Although this method is not sufficiently concrete to allow the actual construction of effective field theories, the gross understanding of their usefulness becomes clear through an RG analysis. This method also lends credence to the main technique of constructing effective field theories, through the analysis of symmetries. If there is a single mass scale M''' in the microscopic theory, then the effective field theory can be seen as an expansion in '''1/M. The construction of an effective field theory accurate to some power of 1/M requires a new set of free parameters at each order of the expansion in 1/M. This technique is useful for scattering or other processes where the maximum momentum scale k''' satisfies the condition '''k/M≪1. Since effective field theories are not valid at small length scales, they need not be renormalizable. Indeed, the ever expanding number of parameters at each order in 1/M required for an effective field theory means that they are generally not renormalizable in the same sense as quantum electrodynamics which requires only the renormalization of two parameters. Υποσημειώσεις Εσωτερική Αρθρογραφία *Φυσικό Πεδίο *Φυσική Θεωρία *Κλασσική Πεδιακή Θεωρία *Σχετικιστική Πεδιακή Θεωρία *Κβαντική Πεδιακή Θεωρία *Τοπολογική Πεδιακή Θεωρία (Topological field theory ) *Σύμμορφη Πεδιακή Θεωρία (conformal field theory) * Κρυσταλλική Πεδιακή Θεωρία (Crystal field theory) * Effective field theory * Unified field theory * Mean field theory * Gauge field theory * Ligand field theory * Psychological field theory * Sociological field theory *Class field theory *String field theory *Statistical field theory *Local class field theory *Covariant Hamiltonian field theory *Thermal quantum field theory *Toda field theory *Local quantum field theory *Lattice field theory *Liouville field theory *Noncommutative quantum field theory *Phenomenal field theory *Polymer field theory *Qubit field theory *Decision field theory *Lexical field theory *Dynamical mean field theory *Algebraic quantum field theory *Constructive quantum field theory *Rational conformal field theory *Irrational conformal field theory *Logarithmic conformal field theory *Boundary conformal field theory Βιβλιογραφία * * Ιστογραφία *Ομώνυμο άρθρο στην Βικιπαίδεια *Ομώνυμο άρθρο στην Livepedia * Intro to Effective Field Theories and Inflation *[ ] Category:Πεδιακές Θεωρίες